Maternal vitamin D deficiency during pregnancy has been linked to fetal growth and may also impact child growth in infancy. We used data and blood samples from the 12‐site U.S. Collaborative Perinatal Project (1959‐65) to examine the association of maternal vitamin D status during pregnancy and infant anthropometry across the first year of life in singletons (n=2473 mother‐child pairs). Maternal serum 25‐hydroxyvitamin D (25(OH)D) was measured at 蠄26 weeks gestation using chromatography‐tandem mass spectrometry. Infant anthropometry was expressed as z‐scores for length (LAZ), head circumference (HC‐Z), weight (WAZ), and BMI (BMI‐Z) based on measures at birth and 4, 8 and 12 months of age. We controlled for study site, and important infant and maternal characteristics in linear mixed effects models. 25(OH)D <30 nmol/L (conventional definition of deficiency) vs. 蠅30 nmol/L was associated with LAZ and HC‐Z measures that were 0.13 (95% CI: 0.03‐0.23) and 0.20 (95% CI: 0.11‐0.28) lower, respectively, across the first year of life. Differences observed by 25(OH)D in WAZ and BMI‐Z at birth resolved by 4 months of age, potentially reflecting catch‐up growth. These findings suggest that maternal vitamin D deficiency has a sustained association with markers of linear or skeletal growth during the first year of life, while initial associations with measures of weight and body composition may resolve.Grant Funding Source: Supported by R01 HD 056999